The necessity of a traditional telephone connection for facsimile transmission is a central consideration when evaluating methods for sending and receiving documents. Older fax machines were designed to transmit data via analog signals, requiring a direct connection to a landline phone service. These devices convert digital information into audio tones that are then sent over the phone network to a receiving fax machine, which reverses the process to reconstruct the original document.
Historically, the reliance on a physical phone line provided a dedicated pathway for fax communication, ensuring a relatively secure and reliable transmission. The widespread availability of landline service made faxing a ubiquitous method for document exchange in business and personal contexts. However, this dependency also presented limitations, including the inability to transmit faxes during phone calls and the added expense of maintaining a dedicated phone line solely for fax purposes.